1. Field of the Disclosure
This specification relates to an organic light emitting display device and a fabricating method thereof, and more particularly, to an organic light emitting display device capable of preventing an occurrence of deterioration or defect due to permeation of air or moisture through cracks formed on a passivation layer, and a fabricating method thereof.
2. Background of the Disclosure
In recent time, various types of flat panel display devices capable of reducing weights and volumes, which are disadvantages of a cathode ray tube, are being developed. Examples of the flat panel display device include a liquid crystal display (LCD) device, a field emission display device, a plasma display panel, an organic light emitting display device, and the like.
Among those flat panel display devices, the plasma display device is focused on as a display device, which is light, thin, short and small and the most advantageous for providing a large-scaled screen, by virtue of simplified structure and fabricating processes. However, the plasma display device also has disadvantages in view of low luminous efficiency and brightness and high power consumption. On the other hand, the LCD device has disadvantages in view of being difficult to implement a large screen due to the use of a semiconductor process and causing high power consumption due to a backlight unit. Also, the LCD device exhibits a great optical loss and a narrow viewing angle due to optical elements, such as a polarizing filter, a prism sheet, a diffusion plate and the like.
On the contrary, light emitting display devices are classified into an inorganic light emitting display device and an organic light emitting display device according to a material of a light emitting layer. The organic light emitting display device is a self-light emitting device, which has great advantages in the aspects of fast response speed, high luminous efficiency, high brightness, and a large viewing angle. The inorganic light emitting display device causes high power consumption and is unable to obtain high brightness, as compared with the organic light emitting display device. Also, the inorganic light emitting display device cannot emit light with various colors of red (R), green (G) and blue (B). On the other hand, the organic light emitting display device is actively being studied by virtue of several advantages, such as being able to be driven by a low DC voltage, which is several tens of volts, having a fast response speed, providing high brightness, and emitting various colors of R, G and B.
Meanwhile, a flexible display device using a flexible substrate, such as a plastic substrate, has been proposed for portability and convenience in use. However, when the flexible substrate is applied to the organic light emitting display device, impurities or foreign materials, such as moisture or air may easily permeate through an upper substrate of the organic light emitting display device because the upper substrate of the display device is also formed of a flexible protection film or the like. Due to the permeation of the impurities such as moisture or air, a defective organic light emitting display device is fabricated and a lifespan of the device is reduced.